package com.hmdp.service.impl;

import cn.hutool.core.bean.BeanUtil;
import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.hmdp.constant.MessageConstant;
import com.hmdp.constant.RedisConstant;
import com.hmdp.dto.Result;
import com.hmdp.dto.UserDTO;
import com.hmdp.entity.Follow;
import com.hmdp.mapper.FollowMapper;
import com.hmdp.service.IFollowService;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.hmdp.utils.RedisIdWorker;
import com.hmdp.utils.UserHolder;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Service;

import javax.annotation.Resource;
import java.util.Collections;
import java.util.List;
import java.util.Set;
import java.util.stream.Collectors;

@Service
public class FollowServiceImpl extends ServiceImpl<FollowMapper, Follow> implements IFollowService {

    @Resource
    private StringRedisTemplate stringRedisTemplate;
    @Resource
    private UserServiceImpl userService;
    @Autowired
    private RedisIdWorker redisIdWorker;

    @Override
    public Result follow(Long followUserId, Boolean isFollow) {
        //1.获取登录用户id
        Long userId = UserHolder.getUser().getId();
        //2.未关注
        if(isFollow){
            //2.1关注 插入数据
            Follow follow = new Follow();
            follow.setUserId(userId);
            follow.setFollowUserId(followUserId);
            boolean save = save(follow);
            if(save){
                //存到redis
                String key = RedisConstant.FOLLOWS +userId;
                stringRedisTemplate.opsForSet().add(key,followUserId.toString());
            }
        }else{
            //2.2取关 删除
            boolean remove = remove(new QueryWrapper<Follow>()
                    .eq("user_id", userId)
                    .eq("follow_user_id", followUserId));
            //从Redis中移除
            if (remove) {
                stringRedisTemplate.opsForSet().remove(RedisConstant.FOLLOWS +userId);
            }
        }
        return Result.ok();
    }

    @Override
    public Result isFollow(Long followUserId) {
        Long userId = UserHolder.getUser().getId();
        Integer count = query().eq("user_id", userId)
                .eq("follow_user_id", followUserId).count();
        return Result.ok(count>0);
    }

    @Override
    public Result followCommons(Long id) {
        //获取当前用户
        Long userId = UserHolder.getUser().getId();
        //当前用户
        String key1 = RedisConstant.FOLLOWS +userId;
        String key2 = RedisConstant.FOLLOWS +id;
        //求交集
        Set<String> intersect = stringRedisTemplate.opsForSet().intersect(key1, key2);
        if(intersect==null|| intersect.isEmpty()){
            return Result.ok(Collections.EMPTY_LIST);
        }
        List<Long> ids = intersect.stream().map(Long::valueOf).collect(Collectors.toList());
        List<Object> users = userService.listByIds(ids)
                .stream()
                .map(user -> BeanUtil.copyProperties(user, UserDTO.class))
                .collect(Collectors.toList());
        return Result.ok(users);
    }
}
